HACK: panfrost: add support for custom soft-reset on Amlogic G12

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
chewitt · Mar 13, 2020 · e34cd04 · e34cd04
1 parent 8b9d182
commit e34cd04
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Showing 2 changed files with 16 additions and 1 deletion.
diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
@@ -9,7 +9,9 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 
 #include "panfrost_device.h"
 #include "panfrost_features.h"
@@ -59,7 +61,16 @@ int panfrost_gpu_soft_reset(struct panfrost_device *pfdev)
 
 	gpu_write(pfdev, GPU_INT_MASK, 0);
 	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_RESET_COMPLETED);
-	gpu_write(pfdev, GPU_CMD, GPU_CMD_SOFT_RESET);
+
+	if (of_device_is_compatible(pfdev->dev->of_node, "amlogic,meson-g12a-mali")) {
+		reset_control_assert(pfdev->rstc);
+		udelay(10);
+		reset_control_deassert(pfdev->rstc);
+
+		gpu_write(pfdev, GPU_PWR_KEY, 0x2968A819);
+		gpu_write(pfdev, GPU_PWR_OVERRIDE1, 0xfff | (0x20 << 16));
+	} else
+		gpu_write(pfdev, GPU_CMD, GPU_CMD_SOFT_RESET);
 
 	ret = readl_relaxed_poll_timeout(pfdev->iomem + GPU_INT_RAWSTAT,
 		val, val & GPU_IRQ_RESET_COMPLETED, 100, 10000);

diff --git a/drivers/gpu/drm/panfrost/panfrost_regs.h b/drivers/gpu/drm/panfrost/panfrost_regs.h
@@ -51,6 +51,10 @@
 #define GPU_STATUS			0x34
 #define   GPU_STATUS_PRFCNT_ACTIVE	BIT(2)
 #define GPU_LATEST_FLUSH_ID		0x38
+#define GPU_PWR_KEY			0x050	/* (WO) Power manager key register */
+#define GPU_PWR_OVERRIDE0		0x054	/* (RW) Power manager override settings */
+#define GPU_PWR_OVERRIDE1		0x058	/* (RW) Power manager override settings */
+
 #define GPU_FAULT_STATUS		0x3C
 #define GPU_FAULT_ADDRESS_LO		0x40
 #define GPU_FAULT_ADDRESS_HI		0x44